irqchip/irq-csky-mpintc: Remove unnecessary loop in interrupt handler

csky_mpintc_handler()
  ->handle_domain_irq()
    ->irq_exit()
      ->invoke_softirq()
        ->__do_softirq()
          ->local_irq_enable()

If new interrupt coming, it'll get into interrupt trap before return to
csky_mpintc_handler(). So there is no need loop in csky_mpintc_handler.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/irqchip/irq-csky-mpintc.c

@@ -34,7 +34,6 @@ static void __iomem *INTCL_base;
 #define INTCL_PICTLR	0x0
 #define INTCL_CFGR	0x14
 #define INTCL_SIGR	0x60
-#define INTCL_HPPIR	0x68
 #define INTCL_RDYIR	0x6c
 #define INTCL_SENR	0xa0
 #define INTCL_CENR	0xa4
@@ -75,11 +74,8 @@ static void csky_mpintc_handler(struct pt_regs *regs)
 {
 	void __iomem *reg_base = this_cpu_read(intcl_reg);
 
-	do {
-		handle_domain_irq(root_domain,
-				  readl_relaxed(reg_base + INTCL_RDYIR),
-				  regs);
-	} while (readl_relaxed(reg_base + INTCL_HPPIR) & BIT(31));
+	handle_domain_irq(root_domain,
+		readl_relaxed(reg_base + INTCL_RDYIR), regs);
 }
 
 static void csky_mpintc_enable(struct irq_data *d)